Process of Scab Formation and Scar Formation By: Mariela, Miranda, Ko Meh, Jessica, De’ Corion, & Kyle

What is a Scab? A scab is a dried blood clot that gets hard and forms a crust on the skin where the wound is found. The scabs job is to protect the cut by keeping germs and other bad bacteria out of the wound and give the skin cells underneath a chance to heal.

A scar is the pale pink, brown, or silvery patch of skin that grows in the place where you once had a cut, scrape, or sore. A scar is your skin’s way of repairing itself from injury. What is a Scar?

How Are These Formed?

Scab Formation As soon as you break the skin barrier your body goes straight to work by sticking platelets (Blood Cells) around the wound which causes a clot. The clot acts as a bandage to stop blood and other fluids coming out of the wound. The clot also has fibrin which helps hold the clot together. Even though the clot is formed other events leading to the scab are still occurring. Once the clot starts to get hard and dry out a scab forms Under a scab new skin cells are being made to help repair the skin and damaged blood vessels are being fixed

Scab Formation Continued... -White blood cells start attacking any germs that have gotten into the cut and start to get rid of any dead blood and skin cells that may be around the cut. -By the time the white blood cells are finished a complete new layer of skin will be formed -At the end of the process the scab will fall off to reveal new skin after a week or two. -If you pick or pull up the scab you can undo the repair and rip your skin again taking longer to heal and may even lead to a new scar

Scar Formation Scars are formed when the dermis (deep layer of skin) is damaged. Recreation of collagen occurs during the healing process which is responsible for the creation of a scar. Then your skin starts to make new cells that build up and form a scab which eventually falls off to reveal the scar tissue on the surface of your skin where the injury used to be. The scar will fade over time but it will never match your unharmed skin’s natural tone due to a lack of melanin.

First responders are cells known as neutrophils and these remove foreign materials and bacteria from the wound. The next wave of immune cells to arrive at the scene includes monocytes. These cells normally reside within the spleen and bone marrow but can be mobilized in response to injury or infection. Once in the wound these cells can differentiate into cells called macrophages. Which coordinate the wound healing response. Biochemistry of Scabs

Biochemistry of Scars When the body responds to an injury or to a certain disease it forms scar tissue, the major component is collagen. The collagen in the scar is denser and less elastic than normal tissue and increasing of the cross-linked collagen-abundant scar tissue can cause decrease in physiological function, decreased range of motion in orthopedic conditions and obstructions in internal adhesions.

Interesting Facts The epidermis heals very rapidly after an incision is repaired, which is called epithelialization. Scars take about one full calendar year to completely fade, soften and flatten. Scars that occur in younger and tighter skin tend to heal less well than those that occur in skin that is older & has more wrinkles... There is one great benefit to aging! Scabs and bruises are indicators of healing. The mush of blood cells harden as it dries, forming a clot (scab). Blood clots may form under the skin as well, in the form of black and blue marks or bruises.

Sources http://kidshealth.org/en/kids/scab.html https://www.medicinenet.com/scars/article.htm http://www.biospecifics.com/technology/collagen-and- scar-tissue.html